Statement of the German Child and Adolescent Psychiatrists about ICD-11 Diagnostic Criteria in Anorexia Nervosa

German Child and Adolescent Psychiatrists Comment about ICD-11 Diagnostic Criteria in Anorexia Nervosa

The German Society for Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy (DGKJP) strongly objects the suggested criteria in the upcoming ICD-11 for anorexia nervosa.

Current diagnostic criteria in ICD 10 for anorexia nervosa (AN) (F50.0) are based on different features. These require an underweight specified by a BMI < 17, 5 kg/m² for adults, for children and adolescents a weight less than the tenth percentile of age. Body image disturbances and endocrine disorders, also indicated by a delayed pubertal development, are among the features as well. The ICD-10 diagnostic criteria for AN differentiates between two types of AN, type F50.01 (bingeing-purging type) and type F50.00 (restrictive type).

ICD-11 redefines these criteria and chooses an underweight specified by a BMI < 18,5 kg/m² for adults, whereas children and adolescents have to weigh less than the fifth percentile of age in order to meet the condition (http://www.who.int/classifications/icd/revision/en/). As a consequence, these new criteria will include a larger group of adult patients. By contrast less children and adolescents will fulfill the criteria for AN compared to ICD 10. At the same time, ICD-11 requires that neither another medical condition nor the lack of available food is responsible for underweight. This revision of ICD-10 is guided by the American classification system DSM 5.

The German Association for Child and Adolescent Psychiatry criticizes the weight criterion for children and adolescents. Whereas for adults, many more subjects will be fulfill the criteria for AN than before, the result for children and adolescents will be not to fulfill diagnostic criteria, even if their weight is considerably altered, DSM-5 states that WHO criteria for thinness were adopted (discussing that a BMI between 17.0 kg/m2, and 18.5 might need additional clinical criteria in adults to justify diagnosis), and that “for children, corresponding BMI percentiles should be used”, ICD-11 is now far from using “corresponding” thresholds for children compared to adults: an age percentile lower than 5 does not correspond to a BMI lower than 18.5 kg/m2.This does not take into account that chronically starvation and nutritional deficiency may have even more grave consequences for children and adolescents than for adults.

Instead, we suggest differentiating two types to classify underweight within the ICD-11: Anorexia nervosa with a distinct underweight (BMI < 18,5kg/m² and > 14, 0 kg/m² resp. between the tenth and the 5th BMI-percentiles) and anorexia nervosa with a dangerously low body weight (BMI < 14 kg/m² resp. lower than 3rd percentile of age.